ROLL SAFETY HOUSING Russian patent published in 1998 - IPC

FIELD: safeguarding of pressing devices and rolls against overloading. SUBSTANCE: housing has two side wedges interconnected by bolts. Lower and upper rolling force carrying stop wedges are in contact from the top and from the bottom with side wedges. Bolts are working in tensile mode. When overload occurs in pressure device line, bolts are broken. Upper and lower wedges move one toward another to eliminate overload. Moreover, when pressure screw jams or is pinched between rolls of metal under rolling process, screw is readily released by loosening nuts of connecting bolts of housings and by spreading housing side wedges. To facilitate mounting, side wedges may be brought close one to another. Connecting bolt surface is made smooth to increase their fatigue strength by eliminating stress concentration. Side wedges are connected by three bolts. Central bolt is made from high-strength material, such as alloy steel, and outer connecting bolts are made from plastic materials, such as low-carbon steel. Central bolt carries major part of loading. Upon breakage of central bolt, outer connecting bolts undergo plastic deformation till upper and lower stop wedges come into contact. These bolts are not broken. To facilitate easy mounting of safety housing below pressure screw and withdrawal from under pressure screw, upper and lower stop wedges may be connected by coupling bolts, which may be also used to preliminarily load housing with force making 0.4-0.6 of breaking force to provide prestressing of connecting bolts. To reduce deformation preceding breakage, central bolt may be provided with bore. Such construction allows elastic compliance to be reduced by 1.2-1.3 times, fatigue strength of connecting bolts to be increased by 2.5-3.0 times, dynamic force in pressure device line to be reduced by 4-5 times. EFFECT: increased efficiency, enhanced reliability in operation and simplified replacement of safety housing. 4 cl, 8 dwg